1. Technical Field
The present technology relates to a pneumatic tire, and more specifically, to a pneumatic tire having enhanced braking performance on ice.
2. Related Art
Conventional pneumatic tires include a plurality of circumferential main grooves and block-like land portions that are partitioned by the circumferential main grooves in a tread portion. Additionally, the land portions include a plurality of sipes extending in a tire width direction. Thereby, the edge effect of the tire is enhanced.
However, in recent years, there has been a growing trend toward increasing the number of sipes provided and, while leading to an enhancement in the edge effect of the tire, this also results in problems such as a decline in rigidity of the entire block and a decline in the dry braking performance and braking performance on ice of the tire.
Therefore, in order to solve these problems, a configuration is used in which protrusions and recesses that mutually mate are provided in sipe wall faces. With this configuration, when a tire brakes, the rigidity of the land portion is increased due to the sipes sealing and the protrusions and recesses mating. Thereby, the braking performance on ice of the tire is enhanced. The technology described in Japanese Patent No. 3180160 is known as a conventional pneumatic tire that is configured in this manner.